Problem: What is the least common multiple of 15 and 30? Another way to say this is: $\lcm(15, 30) = {?}$
Solution: The least common multiple is the smallest number that is a multiple of 15 and 30. We know that 15 x 30 (or 450) is a common multiple, but is it the least common multiple? Write out the multiples of 30 until we find a number divisible by 15. 30, So, 30 is the least common multiple of 15 and 30.